Spatial and temporal expression of ligands for CXCR3 and CXCR4 in human endometrium

In this study, we investigated the expression of ligands for CXCR3 (Mig, IP-10, and I-TAC) and CXCR4 (SDF-1) in the human endometrium throughout the menstrual cycle. By immunohistochemistry, immunostaining for Mig and IP-10 was found in the surface epithelia, glandular epithelia, and stroma with some menstrual cycle-dependent fluctuation. By contrast, immunostaining for I-TAC or SDF-1 was not detected. ELISA demonstrated that the concentrations of Mig and IP-10 were higher in the secretory phase than in the proliferative phase, but I-TAC and SDF-1alpha was detected in only a few samples. Endometrial Mig and IP-10 concentrations strongly correlated with the number of endometrial natural killer cells. Progesterone significantly induced Mig secretion and tended to induce IP-10 secretion from the cultured endometrial stromal cells, whereas 17beta-estradiol had no significant effect. Neither I-TAC nor SDF-1alpha was detected in the supernatant of cultured endometrial stromal cells in the presence or absence of 17beta-estradiol or progesterone. The results suggest that Mig and IP-10 may be involved in the recruitment of natural killer cells or other phenomena in the human endometrium.